1. Field of the Invention
The present invention relates generally to electronic parts, and more particularly to an improved heat-dissipating circuit board assembly.
2. Description of the Related Art
A conventional heat-dissipating circuit board assembly is composed of a circuit board and an aluminum board adhered to a bottom side of the circuit board. The aluminum board is disposed with an insulating heat-conducting layer coated on a surface thereof and is adhered to the bottom side of the circuit board by hot pressing in a vacuum machine. The insulating heat-conducting layer not only prevents electrical contacts positioned on the bottom side of the circuit board from short circuit, but also conducts heat generated by heat-generating components of the circuit board to the aluminum board, which dissipates the heat outwards.
However, the aforementioned heat-dissipating circuit board assembly has following drawbacks.
1. The insulating heat-conducting layer is less heat-conductive than metal and has poor tightness and binding strength.
2. The hot-pressing that makes the aluminum board disposed on the circuit board under the vacuum condition is high in production cost but low in yield.
The primary objective of the present invention is to provide a heat-dissipating circuit board assembly, which is effective in heat-dissipation.
The secondary objective of the present invention is to provide a heat-dissipating circuit board assembly, which is low in production cost but high in yield.
The foregoing objectives of the present invention are attained by the heat-dissipating circuit board assembly, which is composed of a heat-conducting base board and a circuit board. The heat-conducting board includes an insulating heat-conducting layer disposed thereon and a plurality of bonding pads disposed on the insulating heat-conducting layer and never connected with one another. The circuit board that is single-layered or multiple-layered includes a plurality of electronic components at at least one side thereof and a plurality of heat-dissipating zones at a side thereof. The heat-dissipating zones are connected with heat-generating elements of the electronic components and correspond to the bonding pads. The heat-conducting base board is connected with the circuit board by the bonding pads that are melted by heating and further disposed therebetween.